#!/bin/bash
# Monitor LVM thin pools - improved to avoid false positives
set -euo pipefail

SEND_NTFY="/usr/local/bin/send-ntfy.sh"

# Check thin pool OVERALL usage (not individual VM disks)
for POOL in $(lvs --noheadings -o vg_name,lv_name,lv_attr 2>/dev/null | grep 't' | awk '{print $1"/"$2}'); do
    # Get data and metadata usage for the POOL itself
    DATA_PERCENT=$(lvs --noheadings -o data_percent "$POOL" 2>/dev/null | tr -d ' ' | sed 's/\..*//')
    META_PERCENT=$(lvs --noheadings -o metadata_percent "$POOL" 2>/dev/null | tr -d ' ' | sed 's/\..*//')
    
    # Skip if empty
    if [ -z "$DATA_PERCENT" ] || [ "$DATA_PERCENT" = "" ]; then
        continue
    fi
    
    POOL_NAME=$(echo $POOL | sed 's/\//--/g')
    
    # Alert on POOL usage, not individual VM disks
    if [ "$DATA_PERCENT" -gt 95 ]; then
        $SEND_NTFY critical "Thin Pool CRITICAL" "🔴 CRITICAL: Thin pool $POOL_NAME DATA at ${DATA_PERCENT}%! ALL VMs on this pool will FREEZE if full!" "skull,error,cd"
    elif [ "$DATA_PERCENT" -gt 90 ]; then
        $SEND_NTFY warning "Thin Pool Warning" "🟡 WARNING: Thin pool $POOL_NAME DATA at ${DATA_PERCENT}% - take action before 95%" "warning,cd"
    fi
    
    if [ -n "$META_PERCENT" ] && [ "$META_PERCENT" != "" ]; then
        if [ "$META_PERCENT" -gt 95 ]; then
            $SEND_NTFY critical "Thin Pool Metadata CRITICAL" "🔴 CRITICAL: Thin pool $POOL_NAME METADATA at ${META_PERCENT}%!" "skull,error,cd"
        elif [ "$META_PERCENT" -gt 90 ]; then
            $SEND_NTFY warning "Thin Pool Metadata Warning" "🟡 WARNING: Thin pool $POOL_NAME METADATA at ${META_PERCENT}%" "warning,cd"
        fi
    fi
    
    logger -t thin-pool-monitor "$POOL_NAME: Data ${DATA_PERCENT}%, Metadata ${META_PERCENT}%"
done

# Separately check for INDIVIDUAL VM disks that are dangerously full
# This is INFO level since the VM can be expanded
FULL_DISKS=$(lvs --noheadings -o lv_name,data_percent 2>/dev/null | grep "vm-" | awk '$2 > 95 {print $1" at "$2"%"}')

if [ -n "$FULL_DISKS" ]; then
    $SEND_NTFY info "VM Disks Nearly Full" "ℹ️ INFO: Some VM disks are >95% full. These can be expanded if needed:\n$FULL_DISKS" "info,cd"
fi